Loans Receivable - Loan Portfolio by Portfolio Segment and by Class of Financing Receivable (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Composition of impaired loans by portfolio segment and by class of financing receivable
Total loans receivable, gross	$ 10,920,452	$ 10,016,392
Allowance for credit losses	118,036	102,241	$ 134,427	$ 57,941
Nonaccrual loans	81,236	158,471	102,832
Loans 90 days past due and accruing	744	331
TDRs	40,681	30,288
Allowance related to TDRs	2,400	4,817
Additional commitments to customers with loans classified as TDRs	404	460
Nonaccrual TDRs	29,239	17,216
Personal Banking:
Composition of impaired loans by portfolio segment and by class of financing receivable
Total loans receivable, gross	6,964,928	6,153,299
Allowance for credit losses	48,887	31,040	30,954	18,356
Nonaccrual loans	15,746	20,098	31,611
Loans 90 days past due and accruing	407	331
TDRs	7,749	8,530
Allowance related to TDRs	1,615	2,160
Additional commitments to customers with loans classified as TDRs	0	0
Personal Banking: \| Residential mortgage loans
Composition of impaired loans by portfolio segment and by class of financing receivable
Total loans receivable, gross	3,498,599	2,994,620
Allowance for credit losses	19,261	7,373	7,266	2,574
Nonaccrual loans	7,574	10,402	15,924
Loans 90 days past due and accruing	0	0
TDRs	6,279	6,749
Allowance related to TDRs	1,069	1,442
Additional commitments to customers with loans classified as TDRs	0	0
Personal Banking: \| Home equity loans
Composition of impaired loans by portfolio segment and by class of financing receivable
Total loans receivable, gross	1,297,674	1,319,931
Allowance for credit losses	5,902	5,300	5,992	3,189
Nonaccrual loans	4,145	5,758	9,123
Loans 90 days past due and accruing	0	0
TDRs	1,470	1,781
Allowance related to TDRs	546	718
Additional commitments to customers with loans classified as TDRs	0	0
Personal Banking: \| Vehicle loans
Composition of impaired loans by portfolio segment and by class of financing receivable
Total loans receivable, gross	2,056,783	1,484,231
Allowance for credit losses	23,059	15,483	14,825	7,292
Nonaccrual loans	3,771	3,263	5,533
Loans 90 days past due and accruing	2	0
TDRs	0	0
Allowance related to TDRs	0	0
Additional commitments to customers with loans classified as TDRs	0	0
Personal Banking: \| Consumer loans
Composition of impaired loans by portfolio segment and by class of financing receivable
Total loans receivable, gross	111,872	354,517
Allowance for credit losses	665	2,884	2,871	5,301
Nonaccrual loans	256	675	1,031
Loans 90 days past due and accruing	405	331
TDRs	0	0
Allowance related to TDRs	0	0
Additional commitments to customers with loans classified as TDRs	0	0
Commercial Banking:
Composition of impaired loans by portfolio segment and by class of financing receivable
Total loans receivable, gross	3,955,524	3,863,093
Allowance for credit losses	69,149	71,201	103,473	39,585
Nonaccrual loans	65,490	138,373	71,221
Loans 90 days past due and accruing	337	0
TDRs	32,932	21,758
Allowance related to TDRs	785	2,657
Additional commitments to customers with loans classified as TDRs	404	460
Commercial Banking: \| Commercial real estate loans
Composition of impaired loans by portfolio segment and by class of financing receivable
Total loans receivable, gross	2,448,028	2,625,481
Allowance for credit losses	44,506	54,141	79,381	15,843
Nonaccrual loans	62,239	129,666	44,092
Loans 90 days past due and accruing	0	0
TDRs	31,980	17,025
Allowance related to TDRs	638	2,024
Additional commitments to customers with loans classified as TDRs	400	400
Commercial Banking: \| Commercial real estate loans - owner occupied
Composition of impaired loans by portfolio segment and by class of financing receivable
Total loans receivable, gross	375,527	390,003
Allowance for credit losses	4,004	3,883	10,518	5,745
Nonaccrual loans	624	1,233	3,642
Loans 90 days past due and accruing	0	0
TDRs	94	159
Allowance related to TDRs	31	24
Additional commitments to customers with loans classified as TDRs	0	0
Commercial Banking: \| Commercial loans
Composition of impaired loans by portfolio segment and by class of financing receivable
Total loans receivable, gross	1,131,969	847,609
Allowance for credit losses	20,639	13,177	13,574	$ 17,997
Nonaccrual loans	2,627	7,474	$ 23,487
Loans 90 days past due and accruing	337	0
TDRs	858	4,574
Allowance related to TDRs	116	609
Additional commitments to customers with loans classified as TDRs	$ 4	$ 60

Financing Receivable, Allowance For Credit Loss, Modifications

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The amount of additional commitments to lend to customers who have financing receivables that have been modified by troubled debt restructurings.

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The non-accruing portion of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings.

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Financing Receivable, Nonaccrual, Including Nonaccrual With No Allowance

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Financing Receivable, Recorded Investment, 90 Days Or More Past Maturity And Still Accruing

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Financing Receivable, Troubled Debt Restructuring, Excluding Nonaccrual

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Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=124255206&loc=SL82895884-210446

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- Definition

Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919230-210447

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=124255206&loc=SL82895884-210446

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 3B
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL120267963-210447

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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